Apparatus for refrigerating systems



, f v 15622376 March 29 1927 fn. DAVENPORT APPARTUS FOR REFRIGERATINGSYSTEMS Filed Sept. 8, 1925 INVENTOR /Pamsom Wave/fpor Patented Mar."29, 1927.

" UNITED STATES iPArENT oFF-ica.

muscu w. Davmrronr, or DETROIT, MIGHIGAN, AssIGNon. To. cnicaeo PNEU-xaTIc Toor. comm, or NEW YORK, 1a. y., A conroaaTIoN or Naw .maantAPPARATUS FOB BEFBIGERATING SYSTEMS.

Applicatien med-September 8, 1925. Serial No. 54,862. I

This invention relates to apparatus for use in mechanical refrigeratorsystems with particular reference to the heat absorbing mem# bers orelements commonly designated as evaporators.

It is customary to design evaporators with sole regard to thequantitative proportioning of their internal and external areas, andtheir internal cross section. For example, steam boilers are usually`designed with these points principally in mind. Likewise refrigeratmgboilers or evaporators are usually figured simply on the basisv of totalheat transferring surface.

This invention is particularly -adapted to refrigerating systemsemploying working substances which are slow in evaporating, such asmixtures of liquid, vapor, and gas, and one of its; principal objects isto provide an evaporator adapted to be employed in the cooling ofdomestic refrigerators of the mechanically ,operated type utilizingsuch` a working substance and providing a'- for convectiveconsiderableexternal area heat transfer. y

Evaporators hitherto known or used for this and other similarapplications are not well'=suited to my vpurposes for many reasons. -Allcommon constructions have a broken or irregular external surface-coils,stacks, finned tubes, and the 1ike--, actually amenace to health whenused for'my purposes since l'they cannot be easily kept in a clean andsanitary condition. On the other hand, all known forms in which theexternal surface is smooth and easily cleaned are lackin `in onecharacteristic particularly desirab e where slow evaporating substancesare involved, namely, the length of travel of the working substance,which is required in order that time may be allowed for the liquid toevaporate into equilibrium with the vapxtlir.

' order to illustrate the invention one concrete embodiment thereof isdisclosed in the accompanying drawings -in which:

Fig. 1 is a side lelevational view;

Fig. 2 a vertical transverse sectional view, substantially on the line2-2 of Fig, 1; and

Figs. vational view and a plan view of one Aform X of baille core.

The improved type of evaporator element comprising the present inventionis formed,

3 and 4 are respectively a side ele` as illustrated, of plates of sheetmaterial,

'preferably of metal Aor other suitable heat conducting material,secured together vin face to face engagement and so formed aS to providebetween the plates an elongate pas-v sage, conduit, or chamber,- inwhich liquid refrigerant may be disposed. In the drawing the two platesforming the refrigerating element or evaporator are indicated by thereference characters 3 and 4. In order to provide the elongate fluidpassage between Athe plates at least one of the plates such as v plate3, has raised portions 3. By preference, however, both of the platesforming the element have raised portions 3 .and 4 together in the mannershown the raised portions register in op- A Aposition so thatthevelongate vpassage is disposed partly within both plates.

In order to adapt the evaporator element I to refrigerating systemsutilizing a'workmg substance which 1s slow to evaporate, such as aphysical mixture of a liquid and a gas substantially inert to andinsoluble in the liquid, the passage formed in the element must be ofconsiderable length to provide lthe necessary time factor. The.evaporator element, as illustrated. While the passa ev may be uniform insize or progressive y' larger from end to end or with one or moreprogressively larger portions, it is disclosed in the .drawin ing a-part b of small size adjacent the inlet 5 at the bottom of the elementand a part c ofA larger size taking upthe greater part of the remainder.The upper end of the larger passage c preferably connects with, or opensinto, a chamber d, also formed between the plates 3 and 4 andhavingtherein baille means ein the form of a core extendinglongitudinally of chamber d so that the latter acts as a separatorchamber and prevents entrained liquid from being drawn into the outletpipe 6 which is connected tothe suction side of the compressor or asdifferential in size, hav-` f loo respectively, these raised portionsbeing complementally disposed t erein so that when the plates areassembl y refrigerating system is disclosedin my pump (not shown) of thererigerating apparatus.

AOne simple and economical method of forming the element A is to takesheet metal having the requisite strength and to form the complementalraised portions therein by stamping the plates between (dies. The baiecore e, which may be of an suitablev form such as a mass vof spaced pates, is secured in proper position toone of the plates and then the twoplates are assembled in face engagement withl the raised portionsthereof in opposed registration as indicated in Fig. 2. The plates maybe secured together in any desired manner as by welding, soldering, andeven by crimping the edges as indicated in the drawing if suitablesealing material impervious to the working substance is used to sealvthe plates adjacent the continuous passage formed by raised portions band c. After the element A has been formed, its

external surface may be treated, if necessary or desirable, in anydesired manner to give it a smooth and easily cleaned surface, onemethod being to coat the exterior with vitreous enamel. One way ofinstalling the ele-` ment and connecting it into a mechanical eopendingapplication Ser. No. 47,457 filed August l, 1925 entitled Refrigeratingand iee making cabinets.`

. Figs.3 and`4 illustrate a preferred form of baille core e. The coreisv constructed of a plurality of plates f, each corrugated with thecorru ations angularly disposed `relative to the si es of the plate, theplates being so'disposed in face engagement that the corrugat-lons crosseach other as indicated in Fig. 3. The plates are united to form thecore in ,an suitable manner as by having the ends thereof solderedtogether. Such a core provides tortuous passages for the va or, whichis. drawn out of chamber d, an effectively separates from the vaporsubstantially all of the entrainedliquid.

From the above it will be apparent that the present invention disclosesa simple :form of heat absorption element for use in mechanical'refrigerating systems which can be easily and economicallymanufactured, which is adaptable to systems using working substanceswhich evaporate slowly and reuire time for the va or of the liquidreigerant to reach su stantial equilibrium in conformity with the changein temperature, and which presents a smooth exterior surface withoutdeep pockets and inaccessiblecrevices thus enabling it to be easily.kept in a clean and sanitary condition.

am aware that the invention is adapted to varied conditions andusesincluding apparatus for condensing the vaporized refrigerant andthat such adaptations may involve departures from the specific formillustrated in the accompanying drawing comprising two plates of sheetmaterial in' fluid-tight face-to-face engagement at least as to theirperipheral portions. one of said plates being formed with raisedportions providing between the plates an elongate passage,

3. member for use as an element in a mechanically operated refrigeratingsystem comprising two plates of sheet material se# cured together, bothof said plates being stamped to form complemental raised por-4 tions,said plates being secured directly'to each other with their complementalraised portions opposed whereby said plates cooperate to form anelongatepassage therebetween.

"4. A member for use as an element in a mechanically 4operatedrefrigeratin system comprising plates of sheet materia secured" to eachother in yface engagement in a fluidtight manner and rovidingtherebetween an elongate passage iiferential in size.

5. A member fbi' use as an velement in a mechanically operatedrefrigerating system comprising two plates of sheet material securedtogether, onel of said plates being formed with raised portionsproviding bctween the` plates an elongate passage dif.- ferential insize, the Hat portions of said plates being placed together in faceengagement and united in a luid-tight manner.

6. A member for use as an element in amechanically operatedrefrigerating system comprising relatively thinv plates of heatconducting material secured together in face engagement and providingtherebetween an elongate passage enlarged at one` point to form achamber.

7. A meinberfor use as an element in a mechanically operatedrefrigerating system comprising two plates of sheet material se- -curedtogether, one of said plates havingv portionsraised above its plane toform between the latesan elongate assage' having an en argement or cham)er adjacent one end.

les

8. An evaporator for a mechanically A operated refrigerating systemcomprising plates of-sheet material secured together in face engagement`and providing therebeiao \ megeve tween an elongate sinuous passageterminating in an enlargement or chamber, and

b aiile means within said chamber.l

9. An evaporator' for 1i uid refrigerant comprising two plates of heatconducting material secured together in face 'engagement9 said plateshaving complemen al raised portions in' opposed' registration forming anelongated simous passage teru minating at the top of the evaporator in achamber.' the outlet of said evaporator being connected to saidchamber-,and a baie core within said chamber intermediate said outletand said passage to lrevent liquid entrained with the vapor ofta4-refrigerant from passing through said outlet when the,

evaporator is-in use.

10. An evaporator for. liquid refrigerant comprising two` plates ofsheet materlal secured together 1n face engagement, said plates beingstamped to form complemental raised portions sinuous passagedifferential in size and terminating in an enlargement or chamber, theloutlet of said eva orator being connected to 'said chamber, an

chamber intermediate said outlet and said1 passage to prevent liquidentrained with the vapor of the refrlgerant from passing a baie coreWithin said providing an clongate,

g through said outlet when the evaporator is in use. A

1i. A. thin, flat evaporator element formed of sheet material having anelongate fluid passage therein and bame means in a portion of saidpassage.

I12., A thin, flat evaporatorelement formed v of sheet material .andproviding a fluid passage therein of substantial length, said passagebeingenlarged at one point to form achamber. ',w

. 13. A thin, a'teva rator element formed of. sheet material anproviding an elongate 'fluid passage therein differential in size and4terminating at one en'dof said element in an enlargement or chamber.

Ransom W., navarros@l therebetween an elon- M 14. A-thim atevaporatorelement formed f

